Hello,

FLTK is likely the most portable and smallest graphical library for Linux.

Would you know eventually a possible alternative? X/motif?

(avoid gtk or qt dev since it is much too big)

Thank you

Probably TCL/TK.

I mean, that's what they chose for Python's IDLE editor.

Would you maybe another possible alternative? There is actually not much alternatives, right? maybe Xmotif?

Just so you know, the Unity editor was in Xlib for most of its development cycle. If they didn't need to embed a web browser in it, it would still be in Xlib now.

Porting the Unity Editor to Linux: Stuff I Wish We’d Done Then

The last time I wrote anything using Motif it was still fully proprietary - pre Open Motif!

As you have mentioned it a couple of times I have taken a 5 minute refresher course:

X/Motif Programming

It is a little old, like Motfi itself, but still mostly relevant I think.

I second TCL/Tk based only on limited more recent experience.

I have only dabbled with FLTK on occasion.

What exactly are you trying to do with it?

basically, there are qt, gnome gtk, kde libs, fltk, tc/... , and open motif. That's actually all? So far, I think that that's not much.

Oh, I forgot there is too X11, but all will no longer exist, and maybe one day wayland.

And the Enlightenment Foundation Libraries.

There is wxwidgets also, but very heavy.

It also uses GTK widgets on Linux.

so far, we have only FLTK allowing standard, non heavy, possibility, right?

I see not much alternative. I am quite surprise that we have so little options...

Interesting that you won't acknowledge TCL/TK. Maybe you should share the reason you've deemed it unsuitable for what you want to do?

Also: would a TUI (ncurses, etc) be an acceptable option?

The language x11 is quite complex to make gui easily. ex: http://pastebin.com/raw/E92ndwDU

the tcl/tk is quite too heavy, although it gets better.

Think simple, maybe, tiny one like this isn't that bad actually. Not nice, but you won't encounter issues with versions and libraries that changed after time. xmotif is however strongly based on x11.
https://upload.wikimedia.org/wikiped...screenshot.png

Since X11 will disappear, replaced by Wayland, it would be good to have already options. Rewriting code again is nice, but it can be time consuming.

it is that there are no alternatives, the market for such libraries is rather small
and fltk is a nice library.

you could have a look at the fox toolkit if this fits you needs
http://www.fox-toolkit.org/

these days, even embedded devices, if they have a screen where you need a GUI and some interaction, libs like Qt are not a problem in terms of space and functionality, and Qt is probably the most portable, also , Qt , from version 5.8 becomes very modular, so the build can be sized down to what needed better than before.
however, I think, depending on the functionality you need, fltk is nicer to write code with than with Qt

relay light alternatives are maybe something like SDL widgets,
http://members.chello.nl/w.boeke/SDL-widgets/
or other on top of graphic libraries (in game gui took kits)

https://github.com/ocornut/imgui
https://github.com/vurtun/nuklear

You haven't been very specific about your needs, but I think that at least these two qualify as small & portable graphics libs.

Just FYI, the OP periodically posts questions asking for "lightweight" programs/libs. I've never seen any concrete goals/reasons given for it. The most charitable explanation I can come up with is that they want to promote "lighter" programs in general.